biotic, mineral and energy resources | Oceanography | Principle Of Geography

 

Oceanography

Principle Of Geography

Geography Complete Study Material

(Paper - I)

Biotic, Mineral and Energy Resources

             Marine resources are materials and attributes found in the ocean that are considered to have value. That value can be intrinsic, or monetary. They include a huge number of things: biological diversity, fish and seafood supplies, oil and gas, minerals, sand and gravel, renewable energy resources, tourism potential, and unique ecosystems like coral reefs. These resources can have great monetary value, and even when they don’t, the uniqueness and opportunity for education and human enrichment cannot be quantified. The way we manage and use these resources is therefore of great importance. The Ocean is one of Earth’s most valuable natural resources. It provides food in the form of fish and shellfish—about 200 billion pounds are caught each year. Ocean resources provide jobs, goods, and services for billions of people around the world and have immense economic importance. Their resources include food, fuel, renewable energy, minerals, sand and gravel, and tourism. It is mined for minerals (salt, sand, gravel, and some manganese, copper, nickel, iron, and cobalt can be found in the deep sea) and drilled for crude oil. 

Biotic Resources

         Biotic means alive and Abiotic means nonliving. Biotic resources of the seas include fishes, crustaceans, molluscs, corals, reptiles and mammals etc. Alternatively marine biological resources can also be divided into the following 3 categories:

• Planktons 
• Nektons 
• Benthos

Planktons

            Plankton are the diverse collection of organisms found in water that are unable to propel themselves against a current. Phytoplanktons– floating and drifting micro plants. Autotrophs Eg- algae and diatoms Zooplanktons– floating and drifting micro animals. Planktons Communities divided into the following 2 categories.

• Phytoplanktons. 
• Zoo planktons.

Nektons 

                Nekton (or swimmers) are living organisms that are able to swim and move independently of currents at various depths of seas and oceans. Nekton communities divided into 2 types (i) Pelagic fish and (ii) Demersal fish. Pelagic fish live in the pelagic zone of ocean or lake waters – being neither close to the bottom nor near the shore Demersal fish that live on or near the bottom.

• Pelagic fish
• Demersal fish

Benthos

              Benthos is the community of organisms that live on, in, or near the seabed, also known as the benthic zone. This community lives in from tidal pools along the foreshore, out to the continental shelf, and then down to the abyssal depths. Benthos communities divided into three types :

• Epibenthic community. 
• Benthic organisms. 
• Inflora and Infauna.

Mineral Resources

         (A) On the basis of location: 

(i) Minerals of the continental shelf deposits :- 1. Salt 2. Bromine 3. Magnesium 4. Gold 5. Zinc 6. Uranium 7. Thorium

(ii) Minerals of the continental slope deposits :- Sulfur – associated with marine volcanism. Ex. Gulf of Mexico – a rich source of sulfur, monazite sand (source of thorium) at Kerala coast, Gold (Alaska), Zircon (Brazil, Australia), Diamond (SouthAfrica), Calcium-– Peruvian coast rich deposits of calcium and phosphate, Sand and gravel – significant building materials widely found on beds of continental shelves, Fishes are rich in nitrate and phosphate, high protein, medicinal use, Pearls

(iii) Minerals of the deep sea bottom deposits :- Manganese nodules– It comprises several minerals like nickel, copper, cobalt, lead, zinc, etc. Go to Store The maximum percentage of Iron and Manganese. Cobalt-rich marine deposits associated with seamounts and guyots. Phosphate-in form of phosphoritic modules on shallow seabeds. Polymetallic nodules Polymetallic nodules are rounded accretions of manganese and iron hydroxides that cover vast areas of the seafloor but are most abundant on abyssal plains.

       (B) On the basis of nature: 

(i) Metallic minerals. 

(ii) Fuel minerals (petroleum, natural gas). 

(iii) Construction materials (gravels, sands etc.).

Energy Resources

         (A) Conventional energy: 

(i) Petroleum. 

(ii) Natural gas. 

        (B) Non-conventional energy: 

(i) Tidal energy :- Tidal energy is produced through the use of tidal energy generators. Large underwater turbines are placed in areas with high tidal movements and are designed to capture the kinetic motion of ocean tides in order to produce electricity.

(ii) Wave energy :- Wave energy is produced when electricity generators are placed on the surface of the ocean. The energy provided is most often used in desalination plants, power plants, and water pumps. Energy output is determined by wave height, wave speed, wavelength, and water density.

(iii) Biomass energy :- Ocean thermal energy conversion (OTEC) uses the temperature difference between a cooler deep and warmer shallow or surface seawaters to run a heat engine and produce useful work, usually in the form of electricity. However, since the temperature differential is small, the thermal efficiency is low, making its economic feasibility a challenge.